Electrophysiological signals are sensed in a variety of applications, including electroencephalography, electrocardiography, electromyography, electrooculography and the like. In some applications, line filters may be incapable of removing noise caused by certain influencing factors, such as frequency shift and the like. Since most existing approaches utilize frequency based approach, for a selected small interval, artifacts from interval boundaries can contaminate the filtering results across the whole interval. This contamination tends to be more detrimental as the level of information being extracted from the signals increases.